Doors for rubber mixers or the like



Aug. 1, 1961 R. N. COMES ETAL DOORS FOR RUBBER MIXERS OR THE LIKE 3Sheets-Sheet 1 Filed Nov. 6, 1958 INVENTORS i W f q 7 ATTORNEYI) Aug. 1,1961 R. N. COMES ET AL DOORS FOR RUBBER MIXERS OR THE LIKE 3Sheets-Sheet 2 Filed NOV. 6, 1958 INVENTOR ATTORNEYS Aug. 1, 1961 R. N.COMES ET AL DOORS FOR RUBBER MIXERS OR THE LIKE 3 Sheets-Sheet 3 FiledNov. 6, 1958 INVENTORS L ATTORNEYS DOORS FOR RUBBER MIXERS OR THE LIKERichard N. Comes, Wocdbridge, and Richard W. Fuller,

Orange, Conn., assignors to Farrel-Birmingham Company, Incorporated,Ansonia, Conn., a corporation of Connecticut Filed No 6, 1958, Ser. No.772,383 8 Claims. (Cl. 18-2) This invention relates to rubber mixers ormixers for converting materials into a plastic mass. Such devicesgenerally comprise a chamber into which the material is fed and bladedrotors are mounted to rotate within the chamber to mix and knead themate ial. The chamber is usually provided with a lower discharge openingthrough which the material is discharged when it has been mixed, andthis opening is usually closed by a discharge door movably mounted onthe frame of the machine so that it may be moved from open to closedposition.

In many instances a sliding door has been employed for closing the lowerdischarge opening of the chamber but a swinging door is sometimespreferred in that it may be moved in position to make a tight fit withthe Walls of the chamber surrounding the discharge opening with lessfriction than is present when a sliding door is employed. As hereinillustrated, a swinging door is employed to close the opening in thechamber and this door swings about a horizontal axis transverse to thehorizontal axes of the rotors.

Means are provided to move the door to open and closed positions andmeans also are preferably provided to lock or cam the door in closedposition so that it makes a tight fit in order to prevent escape fromthe chamber of the materials which are in some instances finely dividedmaterials. The swinging door itself as well as the operating meanstherefor are in the present instance carried by a frame which may bemounted below the mixing chamber, this frame having an upper base memberprovided with an opening through which the door swings and through whichthe material may drop in its escape from the chamber. The presentconstruction provides a particularly expedient device to be applied toexisting machines so as to permit the use of a drop door on suchmachines where one is not already employed.

One object of the present invention is to provide a mixer for rubber orlike material having a chamber provided with a lower discharge openingand a swinging door to close this opening, the door being pivotallymounted to swing about an axis transverse to the axes of the rotorsprovided in the mixing chamber.

A still further object of the invention is to provide a rubber mixerwith a drop door or swinging door for the discharge of the material fromthe chamber of the mixer and operating means for moving the door to openand closed position wherein the door and its operating mechanism ismounted upon a frame which may be designed to fit existing installationsso as to equip such installations with a door of this character.

Still another object of the invention is to provide a mixing chamber forplastic materials having a lower discharge opening and rotors within thechamber with a swinging door to close the discharge opening of thechamber and hydraulic means to actuate the door, the door and itsoperating means being carried by a frame providing for the passage ofthe discharged material therethrough, the door being mounted to swingdownwardly about a horizontal axis adjacent one end of the chamber.

Still another object of the invention is to provide a swinging dischargedoor for the chamber of a rubber mixer or the like with means foractuating the door to and from closed position and means for locking thedoor States Patent were in closed position so as to assure a tight fitbetween the door and the edges of the chamber opening to be closed bythe door.

To these and other ends the invention consists in the novel features andcombinations of parts to be hereinafter described and claimed.

in the accompanying drawings:

FIG. 1 is a side elevational view, partly in section, of a mixer forrubber or like material embodying our invention showing the dischargedoor in closed position;

FIG. 2 is a view similar to FIG. 1 showing the door and door operatingmechanism in open position;

FIG. 3 is an end view of the mechanism, some parts being shown insection; and

FIG. 4 is a top plan view of the door-supporting frame and associatedparts.

To illustrate a preferred embodiment of the invention there is shown inthe drawings a mixer for rubber or like material provided with a mixingchamber designated generally by the numeral 10, which chamber is ofdoublecylindrical shape and provided with rotors 11 and 12 which arerotatably mounted in the chamber on horizontal axes. As shown moreespecially in FIGS. 1 and 3, the chamber is provided with a lowerdischarge opening 13 adapted to be closed by a door structure 14. Asillustrated, the door is provided with curved side walls 15 and 16, theupper surfaces of which complement the inner surfaces of the walls ofthe chamber, although a known type of V-type door may be employed ifdesired.

The door member is secured to a door support 17 which is pivotallymounted upon a pivot pin 18 carried by brackets 19 and 20 (FIG. 3)upstanding from a base member 21. The door support 17 is provided withdown wardly projecting flanges 22, these flanges being inclined at theirrear ends, as shown at 23, and provided with a wear plate 24 for apurpose to be hereinafter described.

The base plate is provided with an opening 25 which registers with theopening 13 of the chamber so that the door 14 and door-supporting member17 may swing downwardly through this opening as shown in FIG. 2 andpermit the discharge of the material from the chamber when that isdesired. It will, of course, be understood that the end portions of thedoor are properly formed to fit closely the end walls 26 and 27 of thechamber (FIG. 1) so that the chamber opening will be tightly closed whenthe door is in closed position. The base member or base plate 21 is inturn supported upon a bed designated generally by the numeral 28 whichalso supports the chamber 10, this bed being cored out to permit thedoor and associated parts to drop downwardly and also to support thedoor-operating means.

Secured to and depending downwardly from the base plate 21 are a pair ofspaced side plates 29, these plates being spaced sufficiently far apartthroughout the greater part of their lengths to lie outwardly of theopening 25, as shown more especially in FIG. 4. At their forward ends,the left-hand ends as shown in FIG. 4, they are offset inwardly at 30 toprovide more closely spaced, substantially parallel end portions 31. Acylinder 32 is pivoted to the members 31 upon trunnions 33 so that thecylinder is permitted a swinging movement during movements of the door.A piston 34 is slidably mounted in the cylinder, the free end of whichextends upwardly between the flanges 22 of the door-supporting memberand is pivoted thereto at 35. Fluid pressure, which may be hydraulicpressure or compressed air, is admitted to the ends of the cylinder 32on one side or the other of the piston head by flexible tubes 36 and 37,the ends of which may lead to a junction block 38 where they may beconnected by suitable valves, not shown, with a source of fluidpressure.

At its rear end the base plate 21 is provided with a pair of upstandingflanges 39 between which is pivoted on trunnions 40 a cylinder 41 havinga cooperating piston 42. Fluid pressure, either compressed air orhydraulic pressure, may be carried to the ends of the cylinder onopposite sides of the piston by the flexible conduits 43 and 44, whichconduits, as shown in FIG. 4, also may lead to the junction block 38.The free end of the piston 42 is pivotally connected to a pivot pin 45carried by the arms 46 of a member 46 pivoted upon a pivot pin 47carried by the members 29. Upon the pivot pin 45 are rollers 48 whichare adapted to engage the wear plate 24 upon the door support 17 andlock the door in closed position and at the same time cumming the doortightly closed.

Thus the base plate 21 together with the side plates 29 comprise a framewhich is readily mounted on the bed 28 and which frame serves to mountthe swinging door and the operating means therefor to permit convenientapplication of a swinging door to a mixer originally supplied with adoor of some other type such as a sliding door, for example. Theoperating cylinders 32 and 41 are pivotally carried by this frame as isalso the door so that these parts may be assembled and installed as aunit on the bed 28.

As shown in FIG. 1 of the drawing, the door is in closed position andboth pistons 34 and 42 are in their extended positions. To move the doorto open position and permit discharge of the material in the chamber,pressure fluid is admitted to the cylinder 41 through the conduit 43,thus driving the piston rearwardly and moving the arms 46 and therollers 48 to the position shown in FIG. 2 in which the door is unlockedand free to swing to its open position.

Pressure fluid is thereupon admitted through the conduit 37 to thecylinder 32, retracting the piston 34 and moving the door downwardly tothe position shown in FIG. 2. It will be understood that during thepivotal movements of the arms 46 and the door 17 the cylinders alsopivot to some extent about the trunnions 33 and 40.

To close the door, pressure fluid is admitted through the conduit 36,the other end of the cylinder being exhausted through the conduit 37,and the piston 34 is protracted to swing the door upwardly to theposition shown in FIG. 1, after which pressure fluid is admitted throughthe conduit 44 to drive the piston 42 outwardly and cause the rollers 48to engage the wear plate 24 and lock the door tightly in closedposition. The cylinder 32 is conveniently mounted below the plate 21 ina cored-out portion of the bed which permits movement of the cylinder asrequired during swinging movements of the door while the cylinder 41 ismounted above the base plate 21 but supported thereby so that the doorand all of the door-operating mechanism are mounted on the base plate 21of the frame which, as previously stated, may be readily installed uponan existing machine, the frame being designed to fit upon an existingbed.

While we have shown and described a preferred embodiment of ourinvention, it will be understood that it is not to be limited to all ofthe details shown, but is capable of modification and variation withinthe spirit of the invention and within the scope of the claims.

What We claim is:

1. A mixer for plastic materials comprising a chamber having a bottomdischarge opening, a rotor element rotatably mounted in the chamber, abed upon which said chamber is supported, a frame mounted upon the bedand having an upper base plate provided with an opening in registrationwith, and disposed below, the discharge opening of the chamber, a doormember closing the discharge opening, a door-supporting member upon theupper surface of which the door is carried, means for pivoting thedoor-supporting member to the frame below and in registration with thedischarge opening to swing through said plate opening about an axistransverse to the axis of the rotor element, and fluidpressure-actuatedmeans to move said door-supporting member about its pivot to open andclosed positions of the door, said last-named means being carried by theframe below said base plate.

2. A mixer for plastic materials comprising a chamber having a bottomdischarge opening, a rotor element rotatably mounted in the chamber, abed upon which said chamber is supported, a frame mounted upon the bedand having an upper base plate provided with an opening in registrationwith, and disposed below, the discharge opening of the chamber, a doormember closing the discharge opening, a door-supporting member upon theupper surface of which the door is carried, means for pivoting thedoor-supporting member to the frame below and in registration with thedischarge opening to swing through said plate opening about an axistransverse to the axis of the rotor element, fluid-pressure-actuatedmeans to move said door-supporting member about its pivot to open andclosed positions of the door, said lastnamed means being carried by theframe below said base plate, a locking element pivoted to the frame andadapted to engage the door-supporting member at a point remote from itspivot to lock the door in closed position, and fluid-pressure-actuatedmeans carried by the frame to actuate said locking element.

3. A mixer for plastic materials comprising a chamber having a bottomdischarge opening, a rotor element rotatably mounted in the chamber, abed upon which said chamber is supported, a frame mounted upon the bedand having an upper base plate provided with an opening in registrationwith, and disposed below, the discharge opening of the chamber, a doormember closing the discharge opening, a door-supporting member upon theupper surface of which the door is carried, means for pivoting thedoor-supporting member to the frame below and in registration with thedischarge opening to swing through said plate opening about an axistransverse to the axis of the rotor element, fluid-pressure-actuatedmeans to move said door-supporting member about its pivot to open andclosed positions of the door, said last-named means being carried by theframe below said base plate, said fluid-pressure-actuated meanscomprising a piston carried by the cylinder and pivotally connected tothe door-supporting member, spaced side plates secured to the base plateand depending therefrom, and said cylinder being pivotally mountedbetween said side plates.

4. A mixer for plastic materials comprising a chamber having a bottomdischarge opening, a rotor element rotatably mounted in the chamber, asupporting bed upon which the chamber is mounted, a door-supportingframe, means for securing said frame to the bed at the upper surfacethereof below the chamber, a door structure, means for pivoting saiddoor structure to the frame at a point below and in registration withthe discharge opening to swing to a position against the chamber toclose the discharge opening and to an open position with respect to saidopening, and means carried by the frame for swinging said door structureabout its pivot.

5. A mixer for plastic materials comprising a chamber having a bottomdischarge opening, a rotor element rotatably mounted in the chamber, asupporting bed upon which the chamber is mounted, a door-supportingframe, means for securing said frame to the bed at the upper surfacethereof below the chamber, a door structure, means for pivoting saiddoor structure to the frame at a point below and in registration withthe discharge open ing to swing to a position against the chamber toclose the discharge opening and to an open position with respect to saidopening, and fluid-pressure means mounted on the frame for swinging saiddoor structure about its pivot.

6. A mixer for plastic materials comprising a chamher having a bottomdischarge opening, a rotor element rotatably mounted in the chamber, asupporting bed upon which the chamber is mounted, a door-supportingframe, means for securing said frame to the bed at the upper surfacethereof below the chamber, a door structure, means for pivoting saiddoor structure to the frame at a point below and in registration withthe discharge opening to swing to a position against the chamber toclose the discharge opening and to an open position with respect to saidopening, fluid-pressure means mounted on the frame for swinging saiddoor structure about its pivot, said fluid-pressure means comprising acylinder pivoted to the frame and a piston in the cylinder pivotallyconnected to the door structure, and said door structure being pivotedto the frame about an axis transverse to that of the rotor element.

7. A mixer for plastic materials comprising a chamber having a bottomdischarge opening, a rotor element rotatably mounted in the chamber, asupporting bed upon which the chamber is mounted. a door-supportingframe, means for securing said frame to the bed at the upper surfacethereof below the chamber, a door structure, means for pivoting saiddoor structure to the frame at a point below and in registration withthe discharge opening to swing to a position against the chamber toclose the discharge opening and to an open position with respect to saidopening, fluid-pressure means mounted on the frame for swinging saiddoor structure about its pivot, and

means carried by the frame and engaging the end portion of the doorstructure remote from its pivot to lock it in closed position.

8. A mixer for plastic materials comprising a chamber having a bottomdischarge opening, a rotor element rotatably mounted in the chamber, asupporting bed upon which the chamber is mounted, a door-supportingframe, means for securing said frame to the bed at the upper surfacethereof below the chamber, a door structure, means for pivoting saiddoor structure to the frame at a point below and in registration withthe discharge opening to swing to a position against the chamber toclose the discharge opening and to an open position with respect to saidopening, fluid-pressure means mounted on the frame for swinging saiddoor structure about its pivot, means carried by the frame and engagingthe end portion of the door structure remote from its pivot to lock itin closed position, said last-named means comprising a cam memberpivoted on the frame and adapted to engage the door structure, andfluid-pressure means mounted on the frame to move said cam member to andfrom engaging position.

References Cited in the file of this patent UNITED STATES'PATENTS742,971 Cummer Nov. 3, 1903 1,227,522 Banbury May 22, 1917 1,234,526Banburg July 24, 1917

